Deck 26: The Refraction of Light: Lenses and Optical Instruments

Question 1

A beam of light passes from air into water. Which is necessarily true?

A)The frequency is unchanged and the wavelength increases.
B)The frequency is unchanged and the wavelength decreases.
C)The wavelength is unchanged and the frequency decreases.
D)Both the wavelength and frequency increase.
E)Both the wavelength and frequency decrease.

Answer 1

The frequency is unchanged and the wavelength decreases.

Question 2

What is the frequency of light that has a wavelength in water of 788 nm if the refractive index for this light is 1.33?

A)3.76 × 10¹⁴ Hz
B)5.00 × 10¹⁴ Hz
C)6.65 × 10¹⁴ Hz
D)2.86 × 10¹⁴ Hz
E)9.52 × 10¹⁴ Hz

Answer 2

2.86 × 10¹⁴ Hz

Question 3

The table lists the index of refraction for various substances at 20 °C for light with a wavelength of 589 nm in a vacuum. Through which substance will light with a vacuum wavelength of 589 nm travel with the greatest speed?

A)fused quartz
B)crown glass
C)ethyl alcohol
D)carbon tetrachloride
E)crystalline quartz

Answer 3

ethyl alcohol

Question 4

A ray of light propagates in water (n = 1.333) and strikes a sheet of crown glass (n = 1.523). If the angle of refraction in the glass is 35.2°, determine the angle of incidence.

A)30.3°
B)32.8°
C)35.2°
D)41.2°
E)45.0°

Question 5

The bending of light as it moves from one medium to another with differing indices of refraction is due to a change in what property of the light?

A)amplitude
B)period
C)frequency
D)speed
E)color

Question 6

The speed of light in material A is 1.4 times as large as it is in material B. What is the ratio of the refractive indices, n_A/n_B, of these materials?

A)1.4
B)1.2
C)1.0
D)0.80
E)0.71

Question 7

A ray of light originates in medium A and is incident upon medium B. For which one of the following pairs of indices of refraction for A and B is total internal reflection not possible?

A)
B)
C)
D)
E)

Question 8

Which one of the following statements concerning the index of refraction for a given material is true?

A)The index of refraction may be less than 1.
B)The index of refraction may be measured in nanometers.
C)The index of refraction does not depend on the frequency of the incident light.
D)For a given frequency, the index of refraction is inversely proportional to the wavelength of light in vacuum.
E)For a given frequency, the index of refraction is inversely proportional to the wavelength of light in the material.

Question 9

Blue light with a wavelength of 425 nm passes from a vacuum into a glass lens; and the index of refraction is found to be 1.65. The glass lens is replaced with a plastic lens. The index of refraction for the plastic lens is 1.54. In which one of the two lenses does the light have the greatest speed and what is that speed?

A)glass, 2.28 × 10⁸ m/s
B)plastic, 2.13 × 10⁸ m/s
C)glass, 1.82 × 10⁸ m/s
D)plastic, 1.95 × 10⁸ m/s
E)The speed of the blue light is the same in the vacuum and both lenses; and it is 2.99 × 10⁸ m/s.

Question 10

The figure shows the path of a portion of a ray of light as it passes through three different materials. Note: The figure is drawn to scale. What can be concluded concerning the refractive indices of these three materials?

A)n₁ < n₂ < n₃
B)n₁ > n₂ > n₃
C)n₃ < n₁ < n₂
D)n₂ < n₁ < n₃
E)n₁ < n₃ < n₂

Question 11

Light with a wavelength of 589 nm in a vacuum strikes the surface of an unknown liquid at an angle of 31.2° with respect to the normal to the surface. If the light travels at a speed of 1.97 × 10⁸ m/s through the liquid, what is the angle of refraction?

A)19.9°
B)26.1°
C)34.2°
D)39.3°
E)51.9°

Question 12

When certain light rays pass from a vacuum into a block of an unknown material, the measured index of refraction of the material is 3.00. What is the speed of light inside the block?

A)9.9 × 10⁶ m/s
B)4.8 × 10⁷ m/s
C)1.0 × 10⁸ m/s
D)1.9 × 10⁸ m/s
E)2.9 × 10⁸ m/s

Question 13

A ray of light passes from air into a block of glass with a refractive index of 1.59 as shown in the figure. Note: The drawing is not to scale. What is the value of the distance D?

A)1.42 cm
B)1.66 cm
C)1.93 cm
D)2.19 cm
E)2.38 cm

Question 14

The figure shows the path of a ray of light as it travels through air and crosses a boundary into water. The index of refraction of water for this light is 1.33.
What is the angle of refraction for this situation?

A)0.37°
B)0.65°
C)22°
D)41°
E)60°

Question 15

The figure shows the path of a ray of light as it travels through air and crosses a boundary into water. The index of refraction of water for this light is 1.33.
What is the speed of this ray of light as it travels through the water?

A)1.54 × 10⁸ m/s
B)2.26 × 10⁸ m/s
C)2.86 × 10⁸ m/s
D)3.99 × 10⁸ m/s
E)4.43 × 10⁹ m/s

Question 16

A scuba diver shines a flashlight from beneath the surface of water (n = 1.33) such that the light strikes the water-air boundary with an angle of incidence of 37°. At what angle is the beam refracted?

A)31°
B)53°
C)48°
D)65°
E)90°

Question 17

A fish swims 2.00 m below the surface of a pond. At what apparent depth does the fish appear to swim if viewed from directly above? The index of refraction of water is 1.33.

A)1.33 m
B)1.50 m
C)2.00 m
D)2.66 m
E)3.00 m

Question 18

Which one of the following expressions determines the critical angle for quartz (n = 1.5) immersed in oil (n = 1.1)?

A) $\theta$ _c = 1.5/1.1
B) $\theta$ _c = sin^-1 (1.1/1.5)
C) $\theta$ _c = sin (1.1/1.5)
D) $\theta$ _c = tan^-1 (1.1/1.5)

Question 19

A grizzly bear is sitting on a rock in the middle of a calm river when she observes a fish directly below. If the apparent depth of the fish is 0.40 m, what is the actual depth at which the fish is swimming? The index of refraction of water is 1.33.

A)0.80 m
B)0.71 m
C)0.62 m
D)0.53 m
E)0.45 m

Question 20

Complete the following statement: Fiber optics make use of

A)total internal reflection.
B)polarization.
C)chromatic aberration.
D)Brewster's angle.
E)dispersion.

Question 21

A light ray is traveling in a diamond (n = 2.419). If the ray approaches the diamond-air interface, what is the minimum angle of incidence that will result in all of the light reflected back into the diamond? The index of refraction for air is 1.000.

A)24.42°
B)32.46°
C)54.25°
D)65.58°
E)77.54°

Question 22

A beam of light that consists of a mixture of red, green and violet light strikes a prism (surrounded by air) as shown. Indices of refraction for this prism for the various colors are indicated in the table. An observer is located to the right of the prism as shown.
Which physical phenomenon is illustrated by the fact that the observer will not see all three colors of light?

A)Doppler effect
B)dispersion
C)diffraction
D)total internal reflection
E)interference

Question 23

Light is incident at the Brewster angle on a plastic plate in air. The angle of refraction is 35.0°.
Determine the Brewster angle.

A)35.0°
B)55.0°
C)46.5°
D)43.5°
E)82.3°

Question 24

A glass block with an index of refraction of 1.7 is immersed in an unknown liquid. A ray of light inside the block undergoes total internal reflection as shown in the figure. Which one of the following relations best indicates what may be concluded concerning the index of refraction of the liquid, n_L?

A)n_L < 1.0
B)n_L $\ge$ 1.1
C)n_L $\ge$ 1.3
D)n_L $\le$ 1.1
E)n_L $\le$ 1.3

Question 25

Complete the following statement: The term dispersion refers to the fact that the index of refraction of certain materials

A)depends on the Brewster angle.
B)depends on the wavelength of light.
C)depends on the angle of incidence.
D)depends on the intensity of light.
E)depends on the polarization of light.

Question 26

A ray of light originating in oil (n = 1.21) is incident at the Brewster angle upon a flat surface of a quartz crystal (n = 1.458). Determine the angle of incidence for this ray.

A)0.82°
B)1.2°
C)40°
D)50°
E)56°

Question 27

Which one of the following statements is true concerning the focal length of a lens?

A)The focal length is the same for all colors.
B)The focal length is different for different colors because of reflection.
C)The focal length is different for different colors because of dispersion.
D)The focal length is different for different colors because of polarization.
E)The focal length is different for different colors because of spherical aberration.

Question 28

A certain type of glass is used in making flat-panel computer monitors. For light with a wavelength in air of 656.3 nm, the refractive index of the glass is n_A = 1.5160. For light with a wavelength in air of 435.8 nm, n_B = 1.5290. Determine the difference, $\lambda$ _A- $\lambda$ _B, in their wavelengths inside the glass.

A)147.9 nm
B)156.0 nm
C)220.5 nm
D)268.4 nm
E)293.1 nm

Question 29

A beam of light that consists of a mixture of red, green and violet light strikes a prism (surrounded by air) as shown. Indices of refraction for this prism for the various colors are indicated in the table. An observer is located to the right of the prism as shown.
Which color(s) could, in principle, be seen by the observer?

A)only red light
B)only green light
C)only violet light
D)only green and red light
E)only green and violet light

Question 30

Light propagates from soda lime glass (n = 1.518) into Pyrex glass (n = 1.473). Determine the critical angle for this situation.

A)13.99°
B)45.86°
C)52.48°
D)65.22°
E)76.01°

Question 31

A ray of blue light travels through air and is refracted as it enters a glass prism shown in the figure. An unknown liquid is in contact with the right side of the prism. The light then follows the path shown. Which one of the following statements concerning this situation is true?

A)The frequency of the light changes inside the prism.
B)The index of refraction of the glass is smaller than that of air.
C)The index of refraction of the unknown liquid is the same as that of the glass.
D)The speed of light is larger in the liquid than in the glass.
E)The refractive index of the liquid is the same as that of air.

Question 32

White light enters a glass prism, but the color components of the light are observed to emerge from the prism. Which one of the following statements best explains this observation?

A)The separation of white light into its color components is due to the increase in the speed of light within the glass.
B)Some of the color components of the white light are absorbed by the glass and only the remaining components are observed.
C)The index of refraction of the glass depends on the wavelength, so the color components are refracted at different angles.
D)Only some of the color components are refracted by the glass; and these are the ones that are observed.
E)White light is separated into its color components by total internal reflection within the prism.

Question 33

A child is looking at a reflection of the sun in a pool of water. When she puts on a pair of Polaroid sunglasses with a vertical transmission axis, she can no longer see the reflection. At what angle is she looking at the pool of water?

A)45.0°
B)48.8°
C)53.1°
D)61.6°
E)77.3°

Question 34

A ray of light is normally incident on face ab of a plastic prism with an index of refraction n = 1.20 as shown.

-Determine the largest value of the angle $\alpha$ so that the ray is totally reflected at the face ac if the prism is immersed in air.

A)28°
B)34°
C)45°
D)56°
E)Total internal reflection will not occur for any value of $\alpha$ .

Question 35

A fiber optic line is composed of a core with an index of refraction of 1.51 and cladding with an index of 1.40. Which one of the following relations best describes angles of incidence $\theta$ that will result in total internal reflection within the fiber optic line?

A) $\theta$ < 68°
B) $\theta$ > 68°
C) $\theta$ < 22°
D) $\theta$ > 22°
E)0 $\le$ $\theta$ $\le$ 90°

Question 36

A beam of light that consists of a mixture of red, green and violet light strikes a prism (surrounded by air) as shown. Indices of refraction for this prism for the various colors are indicated in the table. An observer is located to the right of the prism as shown.
Which physical phenomenon is illustrated by the fact that the emerging rays are spread into the component colors of the beam?

A)Doppler effect
B)dispersion
C)diffraction
D)total internal reflection
E)interference

Question 37

A beam of light that consists of a mixture of red, green and violet light strikes a prism (surrounded by air) as shown. Indices of refraction for this prism for the various colors are indicated in the table. An observer is located to the right of the prism as shown.
Which physical phenomenon is illustrated by the fact that the prism has different refractive indices for different colors?

A)Doppler effect
B)dispersion
C)diffraction
D)total internal reflection
E)interference

Question 38

A ray of light is normally incident on face ab of a plastic prism with an index of refraction n = 1.20 as shown.

-Determine the largest value of the angle $\alpha$ so that the ray is totally reflected at the face ac if the prism is immersed in a liquid with refractive index 1.12.

A)21°
B)34°
C)69°
D)78°
E)Total internal reflection will not occur for any value of $\alpha$ .

Question 39

What is the Brewster angle when light is reflected from a plastic plate (n = 1.575) submerged in ethyl alcohol (n = 1.362)?

A)68.3°
B)40.8°
C)59.8°
D)30.1°
E)49.1°

Question 40

Light is incident at the Brewster angle on a plastic plate in air. The angle of refraction is 35.0°.
What is the index of refraction of the plastic plate?

A)1.58
B)1.36
C)1.43
D)1.61
E)1.74

Question 41

The figure is a scaled diagram of an object and a converging lens surrounded by air. Only one focal point, F, of the lens is shown.
The index of refraction of this lens is 1.51 for red light and 1.53 for blue light. Blue light is focused at the point F. Which one of the following statements is true concerning the focal point for red light?

A)It is also at F.
B)It is very close to D.
C)It is very close to the lens.
D)It is to the left of and close to F.
E)It is to the right of and close to F.

Question 42

The figure is a scaled diagram of an object and a converging lens surrounded by air. Only one focal point, F, of the lens is shown.
Which pair of terms most accurately describes the image?

A)real, upright
B)real, inverted
C)virtual, upright
D)virtual, inverted
E)virtual, reduced

Question 43

When an object is placed 20 cm from a diverging lens, a reduced image is formed. Which one of the following statements is necessarily true?

A)The image is inverted.
B)The image could be real.
C)The image distance must be greater than 20 cm.
D)The focal length of the lens may be less than 20 cm.
E)The refractive power of the lens must be greater than 0.05 diopters.

Question 44

The system is immersed in a fluid other than air that has an index of refraction that is larger than that of the lens. Which one of the following statements is true concerning this new situation?

A)The image will be real.
B)The image will be inverted.
C)The image will be enlarged relative to the object.
D)The image will be formed on the same side of the lens as the object.
E)The lens may act as a diverging lens or a converging lens depending on the location of the object.

Question 45

An object is placed at the focal point of a converging lens of focal length f. What is the image distance?

A)f
B)2f
C)1/f
D)2/f
E)at an infinite distance

Question 46

A converging lens with a focal length of 12 cm produces a 3-cm high virtual image of a 1-cm high object. Which entry in the table below is correct?

A)
B)
C)
D)
E)

Question 47

Joseph uses a converging lens (f = 0.12 m) to read a map located 0.080 m from the lens. What is the magnification of the lens?

A)+3.4
B)+3.0
C)+1.7
D)+0.60
E)+0.33

Question 48

An object with a height of 4.0 cm is placed 30.0 cm from a lens. The resulting inverted image has a height of 1.5 cm. What is the focal length of the lens?

A)7.5 cm
B)8.2 cm
C)15 cm
D)17 cm
E)21 cm

Question 49

A diverging lens has a focal length of -15 cm. A 5-cm object is placed 35 cm from the lens
What is the magnification of the image?

A)+0.3
B)-0.3
C)+0.7
D)-0.7
E)+0.8

Question 50

A 4-cm object is placed in front of a converging lens of focal length 20 cm. The image is formed 60 cm on the other side of the lens. Which entry in the table below is correct?

A)
B)
C)
D)
E)

Question 51

An object is placed 6.5 cm from a thin converging lens with a focal length of 14 cm. Which one of the following statements is true concerning the image?

A)The image is virtual and 6.0 cm from the lens.
B)The image is virtual and 12 cm from the lens.
C)The image is real and 3.0 cm from the lens.
D)The image is real and 6.0 cm from the lens.
E)The image is real and 12 cm from the lens.

Question 52

A 2.00-cm tall object is placed 40.0 cm from a lens. The resulting image is 8.00-cm tall and upright relative to the object. Determine the focal length of the lens.

A)26.6 cm
B)32.0 cm
C)53.3 cm
D)64.0 cm
E)80.0 cm

Question 53

A camera with a focal length of 0.0500 m (a 50-mm lens) is focused for an object at infinity. To focus the camera on a subject which is 4.00 m away, how should the lens be moved?

A)1.0 cm closer to the film
B)0.06 cm closer to the film
C)4.94 cm closer to the film
D)0.06 cm farther from the film
E)4.94 cm farther from the film

Question 54

A converging lens is used to focus light from a small bulb onto a book. The lens has a focal length of 10.0 cm and is located 40.0 cm from the book. Determine the distance from the lens to the light bulb.

A)8.6 cm
B)13 cm
C)20 cm
D)30 cm
E)50 cm

Question 55

An object is placed at the focal point of a thin diverging lens of focal length f. What is the image distance?

A)f
B)2f
C)1/f
D)f/2
E)at an infinite distance

Question 56

A diverging lens has a focal length of -15 cm. A 5-cm object is placed 35 cm from the lens
Determine the approximate distance between the object and the image.

A)7 cm
B)10 cm
C)18 cm
D)24 cm
E)45 cm

Question 57

When an object is placed 15 cm from a lens, a virtual image is formed. Which one of the following conclusions is incorrect?

A)The lens may be a convex or concave.
B)If the image is upright the lens must be a diverging lens.
C)If the image is reduced, the lens must be a diverging lens.
D)If the lens is a diverging lens, the image distance must be less than 15 cm.
E)If the lens is a converging lens, the focal length must be greater than 15 cm.

Question 58

In a slide projector, the slide is illuminated; and light passing through the slide then passes through a converging lens of focal length 0.10 m. If a screen is placed 5.0 m from the lens, a sharp image is observed. How far is the slide from the lens?

A)0.082 m
B)0.050 m
C)0.50 m
D)0.27 m
E)0.10 m

Question 59

The figure is a scaled diagram of an object and a converging lens surrounded by air. Only one focal point, F, of the lens is shown.
At which of the labeled points will the image be formed?

A)A
B)B
C)C
D)D
E)E

Question 60

When an object is placed 25 cm from a lens, a real image is formed. Which one of the following conclusions is incorrect?

A)The image is upright.
B)The lens is a converging lens.
C)The image may be reduced or enlarged.
D)The image distance can be less than 25 cm.
E)The focal length of the lens is less than 25 cm.

Question 61

The figure is a scaled diagram of a an object and a converging lens. The focal length of the lens is 5.0 units. An object is placed 3.0 units from the lens as shown.
Approximately, what is the image distance?

A)-2.0 units
B)-4.0 units
C)+6.0 units
D)-7.5 units
E)+9.0 units

Question 62

The figure is a scaled diagram of a an object and a converging lens. The focal length of the lens is 5.0 units. An object is placed 3.0 units from the lens as shown.
Where is the final image located relative to the lens on the right?

A)0.08 m to the left of the lens
B)0.12 m to the left of the lens
C)0.08 m to the right of the lens
D)0.12 m to the right of the lens
E)0.36 m to the right of the lens

Question 63

A 4.0-cm object is placed 30.0 cm from a converging lens that has a focal length of 10.0 cm as shown in the diagram. Note: The diagram is not drawn to scale.
A second converging lens is placed 20.0 cm to the right of the lens shown in the figure. Determine the focal length of the second lens if an inverted image (relative to the object in the diagram) is formed 13.3 cm to the right of the first lens.

A)1.33 cm
B)6.67 cm
C)13.3 cm
D)15.4 cm
E)19.7 cm

Question 64

Mrs. McKay has been prescribed eyeglasses with lenses that have a +3.2-diopter refractive power. The glasses are worn 2.0 cm from her eyes. With the lenses, she can read a magazine held 25 cm from her eyes. Which one of the following statements is necessarily true? Note: The near points and far points given in the following answers are measured relative to her eye.

A)She has a far point of 3.2 m.
B)She has a far point of 0.25 m.
C)She has a near point of 3.2 m
D)She has a near point of 6.4 m.
E)She has a near point of 0.87 m.

Question 65

Rachel has a far point of 5 m. Which statement below concerning Rachel's vision is true?

A)She has normal vision.
B)She is myopic and requires diverging lenses to correct her vision.
C)She is myopic and requires converging lenses to correct her vision.
D)She is hyperopic and requires diverging lenses to correct her vision.
E)She is hyperopic and requires converging lenses to correct her vision.

Question 66

A 1.5-cm object is placed 0.50 m to the left of a diverging lens with a focal length of 0.20 m. A converging lens with a focal length of 0.17 m is located 0.08 m to the right of the diverging lens.
What is the location of the final image with respect to the object?

A)The final image is located 0.14 m to the left of the object.
B)The final image is located 0.32 m to the right of the object.
C)The final image is located 0.40 m to the right of the object.
D)The final image is located 0.83 m to the right of the object.
E)The final image is located 1.3 m to the right of the object.

Question 67

The figure is a scaled diagram of a an object and a converging lens. The focal length of the lens is 5.0 units. An object is placed 3.0 units from the lens as shown.
What is the total magnification of this lens combination?

A)+1/2
B)-1/2
C)+1
D)-1
E)+2

Question 68

A 4.0-cm object is placed 30.0 cm from a converging lens that has a focal length of 10.0 cm as shown in the diagram. Note: The diagram is not drawn to scale.
Determine the height and orientation of the image.

A)2 cm and upright
B)1 cm and inverted
C)2 cm and inverted
D)8 cm and upright
E)8 cm and inverted

Question 69

The right lens of Josh's contact lenses is a converging lens of +2.50 diopters. He can read a book held as close as 25 cm from his eyes. Complete the following statement: Without his lenses, Josh's right eye has

A)a far point of 15.4 cm.
B)a far point of 40.0 cm.
C)a far point of 66.7 cm.
D)a near point of 15.4 cm.
E)a near point of 66.7 cm.

Question 70

An object is placed 20.0 cm from a converging lens with focal length 15 cm. A concave mirror with focal length 10 cm is located 75 cm to the right of the lens as shown in the figure. Note: The figure is not drawn to scale.
If the height of the object is 1.0 cm, what is the height of the image?

A)1.2 cm
B)2.4 cm
C)6.0 cm
D)12 cm
E)24 cm

Question 71

The figure is a scaled diagram of a an object and a converging lens. The focal length of the lens is 5.0 units. An object is placed 3.0 units from the lens as shown.
Which pair of terms most accurately describes the image?

A)real, upright
B)real, enlarged
C)real, inverted
D)virtual, inverted
E)virtual, upright

Question 72

A 1.5-cm object is placed 0.50 m to the left of a diverging lens with a focal length of 0.20 m. A converging lens with a focal length of 0.17 m is located 0.08 m to the right of the diverging lens.
What is the height and orientation with respect to the original object of the final image?

A)1.4 cm, inverted
B)1.4 cm, upright
C)0.95 cm, inverted
D)0.95 cm, upright
E)0.28 cm, inverted

Question 73

An object is placed 20.0 cm from a converging lens with focal length 15 cm. A concave mirror with focal length 10 cm is located 75 cm to the right of the lens as shown in the figure. Note: The figure is not drawn to scale.
Which pair of terms most accurately describes the final image?

A)real, upright
B)virtual, upright
C)real, inverted
D)virtual, inverted
E)inverted, enlarged

Question 74

A diverging lens has a focal length of -15 cm. A 5-cm object is placed 35 cm from the lens
Which pair of terms most accurately describes the image?

A)real, upright
B)virtual, upright
C)real, inverted
D)virtual, inverted
E)real, reduced

Question 75

An object is placed 16 cm to the left of a converging lens with a 4.0-diopter refractive power. At what distance from the object will the image be located?

A)14 cm
B)28 cm
C)44 cm
D)56 cm
E)64 cm

Question 76

An object is placed 20.0 cm from a converging lens with focal length 15 cm. A concave mirror with focal length 10 cm is located 75 cm to the right of the lens as shown in the figure. Note: The figure is not drawn to scale.
Determine the location of the final image.

A)48 cm to the right of the lens
B)96 cm to the right of the lens
C)30 cm to the left of the mirror
D)0.225 cm to the left of the mirror
E)0.225 cm to the right of the mirror

Question 77

Andrea's near point is 20.0 cm and her far point is 2.0 m. Her contact lenses are designed so that she can see objects that are infinitely far away. What is the closest distance that she can see an object clearly when she wears her contacts?

A)18 cm
B)22 cm
C)25 cm
D)75 cm
E)180 cm

Question 78

The figure is a scaled diagram of a an object and a converging lens. The focal length of the lens is 5.0 units. An object is placed 3.0 units from the lens as shown.
The object has a height of 1.5 units. What is the approximate height of the image?

A)2.0 units
B)1.2 units
C)5.0 units
D)3.8 units
E)9.8 units

Question 79

A 4.0-cm object is placed 30.0 cm from a converging lens that has a focal length of 10.0 cm as shown in the diagram. Note: The diagram is not drawn to scale.
Where is the image located?

A)15 cm to the left of the lens
B)7.5 cm to the left of the lens
C)7.5 cm to the right of the lens
D)15 cm to the right of the lens
E)30 cm to the right of the lens

Question 80

Without his contact lenses, Mr. Chong can focus from 0.80 m to infinity. What refractive power of the lenses does he require for normal reading (0.25 m from the eyes)?

A)1.25 diopters
B)2.75 diopters
C)4.00 diopters
D)5.25 diopters
E)-5.25 diopters